C - Racism - the belief that some races are superior to others.
Slavery was caused by a need for labor and people to do it other than themselves as people who owned slaves deemed themselves as a savior in a sense.
Racism boosted the need and especially want for slavery. Racism gave the white man an excuse to say that they were superior to African American's, forcing them into a lower class of slaves and working for them.
A would be incorrect as that focused on the economy rather than social standings.
B would be incorrect as that focused on the market and income rather than, yet again, social standards.
D would be incorrect as the enlightenment was more of a golden like age than anything, where people came together to share ideas and opinions while expressing it in different forms.
Hope this helps!
